Applications for optics and optical devices have become numerous and widespread in recent years, expanding upon traditional uses such as telescopes, microscopes and eyeglasses, into various other areas. Cameras and video cameras have become one very popular consumer application, in which precision optics are desired for high-end devices. But imaging optics have played a significant part in modern technology for a wide range of fields, including consumer electronics (e.g., DVD or CD readers, cameras and telescopes), fiber optic communications (e.g., optical couplers and multiplexers), medicine and surgical tools (e.g., precision microscopy, fiber optic probes, MRI and X-Ray machines), military and defense (e.g., laser guided weaponry), and robotics (e.g., artificial sight), as well as a host of other applications. Although modern optical systems are diverse, one of the most interesting recent advancements has been in the field of miniature and micro optics, particularly for digital cameras.
The use of digital imaging sensors and micro optics for cameras and video cameras has made the continuing miniaturization of these devices possible. As a result, camera modules have been integrated into small electronic devices, including hand-held devices such as cell phones, smart-phones and personal digital assistants (PDAs), computing devices such as laptops, net-books and desktop computers, display devices such as televisions, monitors and graphics displays, hidden or inconspicuous surveillance equipment, and so forth. Improvements in image sensors have provided high resolution image detectors utilizing micro-scale pixilation, and at high signal to noise ratio and increasingly lower cost. As digital sensors have improved, advancements in optical systems would be desirable to exploit the potential advantages of high resolution systems.
For example, it would be desirable to have an optical system that can provide enhanced performance and depth of field (EDoF) for a thin and sleek electronic device (e.g., a camera phone) using a high resolution sensor with approximately eight mega pixels. It would also be desirable to have optical systems that can provide the enhanced quality for a range of f-numbers (e.g., between two and three).